Shares of AT&T Inc. T, -0.51% dropped 0.6% in afternoon trading Wednesday, putting them on track to suffer the longest losing streak in a year, and as they headed for the lowest close since July 2010. The stock has shed 7.5% over the past six sessions, which would be the longest stretch of losses since the nine-day loss streak that ended Oct. 21, 2020. The selloff has boosted AT&T’s implied dividend yield to 8.23%, making it the second-highest yielding stock in the S&P 500 SPX, +0.30%, just below fellow communications company Lumen Technologies Inc.’s LUMN, -0.16% yield of 8.27%. That compares with the implied yield for the S&P 500 of 1.39%. AT&T’s stock selloff comes amid growing investor concerns over competition with cable companies, and over ramped up spending by telecommunications companies to build out their fiber networks. Shares of AT&T rival Verizon Communications Inc. VZ, +0.04% slipped 0.3% in Wednesday afternoon trading toward a fifth straight loss and the lowest close since March 2020, while pushing up its implied dividend yield to 5.00%.